Rheumatic Heart Disease-Attributable Mortality at Ages 5-69 Years in Fiji: A Five-Year, National, Population-Based Record-Linkage Cohort Study.

BACKGROUND: Rheumatic heart disease (RHD) is considered a major public health problem in developing countries, although scarce data are available to substantiate this. Here we quantify mortality from RHD in Fiji during 2008-2012 in people aged 5-69 years. METHODS AND FINDINGS: Using 1,773,999 records derived from multiple sources of routine clinical and administrative data, we used probabilistic record-linkage to define a cohort of 2,619 persons diagnosed with RHD, observed for all-cause mortality over 11,538 person-years. Using relative survival methods, we estimated there were 378 RHD-attributable deaths, almost half of which occurred before age 40 years. Using census data as the denominator, we calculated there were 9.9 deaths (95% CI 9.8-10.0) and 331 years of life-lost (YLL, 95% CI 330.4-331.5) due to RHD per 100,000 person-years, standardised to the portion of the WHO World Standard Population aged 0-69 years. Valuing life using Fiji's per-capita gross domestic product, we estimated these deaths cost United States Dollar $6,077,431 annually. Compared to vital registration data for 2011-2012, we calculated there were 1.6-times more RHD-attributable deaths than the number reported, and found our estimate of RHD mortality exceeded all but the five leading reported causes of premature death, based on collapsed underlying cause-of-death diagnoses. CONCLUSIONS: Rheumatic heart disease is a leading cause of premature death as well as an important economic burden in this setting. Age-standardised death rates are more than twice those reported in current global estimates. Linkage of routine data provides an efficient tool to better define the epidemiology of neglected diseases

Rheumatic Heart Disease-Attributable Mortality at Ages 5–69 Years in Fiji: A Five-Year, National, Population-Based Record-Linkage Cohort Study

Background: Rheumatic heart disease (RHD) is considered a major public health problem in developing countries, although scarce data are available to substantiate this. Here we quantify mortality from RHD in Fiji during 2008–2012 in people aged 5–69 years. Methods and Findings: Using 1,773,999 records derived from multiple sources of routine clinical and administrative data, we used probabilistic record-linkage to define a cohort of 2,619 persons diagnosed with RHD, observed for all-cause mortality over 11,538 person-years. Using relative survival methods, we estimated there were 378 RHD-attributable deaths, almost half of which occurred before age 40 years. Using census data as the denominator, we calculated there were 9.9 deaths (95% CI 9.8–10.0) and 331 years of life-lost (YLL, 95% CI 330.4–331.5) due to RHD per 100,000 person-years, standardised to the portion of the WHO World Standard Population aged 0–69 years. Valuing life using Fiji’s per-capita gross domestic product, we estimated these deaths cost United States Dollar $6,077,431 annually. Compared to vital registration data for 2011–2012, we calculated there were 1.6-times more RHD-attributable deaths than the number reported, and found our estimate of RHD mortality exceeded all but the five leading reported causes of premature death, based on collapsed underlying cause-of-death diagnoses. Conclusions: Rheumatic heart disease is a leading cause of premature death as well as an important economic burden in this setting. Age-standardised death rates are more than twice those reported in current global estimates. Linkage of routine data provides an efficient tool to better define the epidemiology of neglected diseases

Flow diagram of ascertainment.

<p>Flow diagram of ascertainment.</p

Characteristics of the cohort by survival.

<p>* Interquartile range;</p><p>† Wilcoxon rank-sum;</p><p>‡ <i>χ</i>² test;</p><p>§ Refers to any of World Heart Federation criteria definite [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0004033#pntd.0004033.ref041" target="_blank">41</a>], moderate or severe mitral regurgitation (MR), or mild MR with two or more morphological features at mitral valve;</p><p>∣∣ During follow-up;</p><p>¶ Before or during follow.</p><p>Characteristics of the cohort by survival.</p

Reported and estimated RHD-attributable deaths by age in Fiji, 2011–2012.

<p>Reported counts are derived from ICD10 coding of underlying cause-of-death classifications in vital registration data. Estimated counts are based on excess deaths in the cohort.</p

Estimated RHD-attributable death rates at ages 5–69 in Fiji, 2008–2012.

<p>A: Death rate, B: YLL rate. Both are plotted at mid-point of age group. Global Burden of Disease (GBD) project estimates for 2010 for all developing countries and for Fiji are plotted for comparison.</p